The head of the Metropolitan Police is to warn that policing in England and Wales is "heading for failure" without urgent reform.

In a speech on Friday, Sir Mark Rowley will call for the system to change, arguing it is unable to cope with the sophistication of modern criminals.

He is proposing eight to 10 regional police forces, supported by hundreds of local policing commands and a new National Police Service, in what would be the biggest overhaul since the 1960s.

The changes would replace the 43-force structure with three tiers: local teams dealing with neighbourhood issues, regional forces sharing specialist resources and a National Police Service tackling the most serious crimes.

Sir Mark says organised crime groups, fraud networks, cyber-criminals and those involved in online child abuse increasingly operate across regional and international borders, while police forces remain organised around local areas.

He will warn that the current system is struggling to keep pace with these threats, saying: "We have 43 overstretched forces trying to do too much, with too little."

He believes merging forces would reduce duplication, arguing this could free up thousands of roles to be redirected towards front line policing.

His proposals follow a consultation launched by Home Secretary Shabana Mahmood in January. This included plans for a National Police Service to tackle the most complex crimes and a possible merger of the 43 forces into fewer, larger forces.

However some rural police and crime commissioners have described the plans as "political manoeuvring" by larger forces to "load the dice in their favour".

The Association of Police and Crime Commissioners (APCC) has also questioned whether merging forces is the best way to improve policing.

It said: "The case for modernisation and a National Police Service is clear. The case for reducing 43 forces to nine regional 'mega-forces' is not."

A Home Office spokesperson defended the plans, saying: "Our current model of policing has not changed since the 1960s and is no longer fit for purpose."

Prime Minister Andy Burnham has not yet commented.

Sir Mark has also highlighted the financial pressures facing policing, asserting that spending on policing had fallen from about 0.9% of GDP to 0.7% since 2010.

He says years of underinvestment have left forces relying on ageing technology, while officers are increasingly diverted from neighbourhood policing to deal with other demands, including mental health and social care.

He will also point to falling police performance, saying positive outcomes nationally are now less than half the level they were 12 years ago, while public confidence has fallen by 9%.

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